J. K. Rowling

Novelist, screenwriter, and film producer.

Challenge: In her 20s, she was a divorced, unemployed single parent who resisted suicidal thoughts only because she needed to care for her infant daughter. She was "as poor as it is possible to be in modern Britain, without being homeless… by every usual standard, I was the biggest failure I knew."

Success: Her Harry Potter series of books have sold more than 400 million copies worldwide and have been translated into 68 languages.

John Green

Writer and vlogger.

Challenge: A former employer called him a "horrible slob" who "didn’t do his job all that well." He was rejected from an advanced creative writing course, dumped by his girlfriend, and took ten years to write one book.

Success: His YouTube channels have millions of subscribers and his books top charts of best sellers.

Jay Z (Shawn Carter)

Rapper, music producer, and entrepreneur

Challenge: He was raised by a single mom in the projects of Brooklyn and dropped out of high school. Later, he was rejected by every major record label and was told the market was too small for his style of music.